Process of and apparatus for treating materials



Dec. 18 1923.

H. D. RANKIN PROCESS OF AND APPARATUS FOR TREATING MATERIALS Filed Oct. 21 1920 IN V EN TOR 11D. Rankzn/ ,4; ATZIORNEYS WITNESS Patented cc. 18, 1923.

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HARRY D. RANKIN, OF CORONADO, CALIFORNIA.

PROCESS OF AND APPARATUS FOR TREATING MATERIALS.

Application filed October 21, 1920. Serial No. 418,476.

T 0 all whom it may concern:

Be it known that I, HARRY D. RANKIN, a citizen of the United States, and a resident of Coronado, in the county of San- Diego, State of California, have invented a certain new and useful Process of and Apparatus for Treating Materials, of which the follow ing is a specification.

The invention relates to a process of and apparatus for treating materials and relates particularly to the fixation of gases, vapors, liquids or solids, or combinations thereof, and more specifically to the fixation or oxidation of nitrogen or the production of en dothermic compounds.

An object of the invention is to provide a process of producing endothermic gaseous or vaporous compounds economically.

Another object of the invention is to provide an apparatus for producing endothermic gaseous or vaporous compounds economically.

A fur 'ther object of the invention is to provide for abrupt and rapid cooling of thegases after the endothermic reaction has occurred.

The invention relates to the fixation of gases, vapors, liquids or solids, or combinations thereof, by the subjection of the materials to an electric arc flame, whereby they are raised to extremely high temperatures, which produce rearrangement of the elements of the materials and then fixing the elements in their resultant rearrangement. I have found it advantageous to economic fixation that the resultant compounds at temperatures of thousands of degrees centigrade be abruptly and rapidly reduced in temperature, to a temperature below that at which any great percentage'of the compounds produced would either dissociate or decompose. For example, in the fixation of nitrogen or the formation of oxides of nitrogen, the temp rature of the resultant gas, should be instantaneously reduced to about 19/00 degrees centigrade. In my prior United States Letters Patent No. 1,150,786, dated August 17, 1915, to which reference is hereby made, I have set forth the necessit of rapidly cooling the resultant materia by any suitable means or method, such as brin ing the material into'contact with a co (1 surface, expanding the material or bringmg it in contact with a cold or expanding %s, and in my United States Patent 0.

1,150,786 of August 17, 1915, I have disclosed a means of cooling, comprising a rheostat for decreasing the electrical energy fed to the arc to reduce the temperature of the arc italf during the cooling part of the cycle. In said patents I have shown several methods of cooling the gases, but I have found that in some instances any one method alone of cooling the ases does not produce a sufliciently abrupt rop in temperature to produce the most economical results. In order to accomplish the desired abrupt drop in temperature of the immediately after they leave the are, I have found it desirable to employ two or more cooling methods or means acting substantially simultaneously on the hot gas, each method su plenienting the other. I have found that in addition to bringing the hot gases incontact with a cooled surface that it is advis- 7 able to produce a substantially concurrent instantaneous expansion of the gases, the instant they leave the arc flame, and if the combination of these two methods is not sufficient, to further and concurrently contact the hot gases from the arc with a material having a great heat absorbing capacit such as air, or water spray or steam or S8, gas or acetic ether or other comparable materials, and if further aid is necessary to 8 reduce energy, i. e., temperature of the are during the cooling part of the cycle. The effect of these two or three or four cooling methods concurrently applied, cools the gaseous material sufficiently to fix the elements owing description, where I shall outline in full the process of my invention and that form of apparatus for car ing out the process which I have select for illustrationin the drawings accompanying and forming part of the present specification. 1%

In said drawings, I have shown one form of apparatus of my invention, but it is to be understood that I do not limit myself to such form since the invention, as set forth in the claims, may be embodied in a plural- 1 ity of forms.

Referring to said drawings:

Figure 1 is a vertical section through one form of apparatus of my invention.

Figure 2 is a vertical section of the upper poxition of the apparatus on an enlarged see c.

Figure 3 is a vertical section thruthe nozzle.

The apparatus comprises a metallic shell 2 provided, if necessary, with a lining of refractory material, such as magnesite brick,

of such thickness to form an arc chamber or insulating material 5, if electrical insulation is essential, and extending into the shell, is a vessel or housing 6 having a throat or passge 7 therein, opening at its lower end into the furnace chamber 4 and opening at its other end into an expansion chamber 8., The space between. the inner and outer walls 12 and l3of the vessel 6 constitutes a water jacket and means are provided for establishing an adequate flow of water through the jacket to keep the wall 12 of thethroat and expansion chamber cool. That is, ordi narily, accomplished by a water inlet pipe 14 discharging adjacent the bottom of the throat and a water outlet pipe 15. The vessel 6 is provided with a flange 16 seating on the insulating ring 5, and is held in place by a clamping plate 17 connected by bolts 18 to a similar clamping plate 19 at the bottom of the she-ll 2.

Extending into the furnace chamber through the expansion chamber 8 is the upper electrode 21, which also extends upwardly through a suitable stuffing box 22. The electrode 21 is preferably metallic and hollow and is preferably provided with means for keeping it cool, but may be made of any suitable material. Extending down into the electrode to the enlarged tip 23 thereof is a water or other cooling medium inlet conduit through which the cooling medium discharges into the electrode. The cooling medium discharges from the electrode through the outlet passage 24 and a sufiicient amount of cooling medium is flowed through the electrode to keep it cool.

Extending into the furnace chamber from below is the lower electrode 25, which has a head 26 of suitable material (according to the reaction sought), which vaporizes at the temperature of the arc to increase the conductivity of the arc gap, or to supply material for reaction, or both. Instead of incorporating these materials in the head of the electrode, they may be introduced into the chamber through a suitable conduit 26 or conduits. These materials, suitable for fixation of nitrogen, are described in my United States Patent No. 1,056,830 of March 25, 1913,?30 which reference is hereby made. The electrode 25 passes through a suitable stufiing box 26 clamped in position by the plate 19 and spaced from the shell 2 by the insulating ring 27 The gases, vapors or other materials to be treated, are introduced into the furnace chamber under pressure, so that a condition of premure exists in the chamber. The materials resultant from contact with the arc flame, or these materials and matter in lower electrode, discharge from the furnace chamber, immediately after they leave the flame, through a relatively narrow opening intothe expansion chamber, wherein the materials expand abruptly and rapidly to many times their former volume. The narrow or small opening through which the materials discharge may be formed in several ways. In Figs. 1 and 2 I have shown a narrow annular opening formed between the tip 23 of the upper electrode and the upper edge of the throat. The narrow opening is-thus formed between the electrode and the throat so that the hot resultant material passes abruptly and rapidly from the flame through the narrow opening and is expanded and cooled. The expansion chamber is provided with a large outlet passage 31 to permitthe free discharge of the cooled gaseous matter therefrom to other devices or containers, to be dealt with as desired. By providing a large expansion chamber outlet, little or slight pressure exists inthe expansion chamber, so that the gaseous matter is free to expand as it issues from. the small opening. The issuing gaseous matter is, therefore, abruptly cooled, immediately after leaving the arc flame, by expansion and by contact with the, watercooled surface to a temperature below that at which any great" percentage of the ma tcrials produced would either dissociate or decompose.

W hen the cooling effect pf these two cool, ing methods acting concurrently, is not sulficient to cause a sufiiciently large and abrupt drop in temperature, the temperature of the gaseous matter may be further reduced by concurrently bringing it into contact with other cooling media, such as set forth herein-- before. This may be accomplished by arranging'an annular chamber 38, provided with an elongated annular discharge 32, in the expansion chamber in such relation to the narrow annular opening throu h which the gaseous matter discharges "mm the throat, that the cooling media discharging from the nozzle impinges against and mixes with the hot gaseous material. The cooling media, which may be air, steam, water spray or other material, as set forth, is introduced into the annular chamber 38 through the conduit 33 under suflicient pressure so that it will discharge against the discharging stream of hot gaseous matter. In the event that the combination of these methods does not produce the desired abrupt temperature drop, the supply of energy to the arc may be cyclically reduced to decrease the temperature of the arc itself.

The gases, liquids, vapors or solids, or combinations thereof to be acted'upon under great pressure, are introduced into the furnace chamber in any suitable manner. Gases, liquids or vapors, may be introduced through pipes 34 extending through the shell and its lining and these pipes may be so disposed at their discharge ends that they discharge the materials tangentially into the furnace chamber, causing them to swirltherein, or they may be so disposed to discharge the material in streams parallel to the arc flame 35, formed between the electrodes, or the materials may be discharged transversely of the arc flame, or in any 'desired direction or combination of directions.

Solid matter to be acted on by the arc,

flame may be introduced in any suitable manner, preferably into the head 26 of the:

lower electrode. For this purpose a feed conduit 20 extends through the easing into proximity with the lower electrode head and this conduit is provided with a suitable check or closure to prevent release of the pressure in the chamber through the conduit. it is not essential that solid material be introduced into the electrode head 26, out. when it is introduced there, it is vaporized readily by the arc and mixes with the other material in the chamber.

The gaseous, liquid, vaporous or solid material is introduced into the furnace chamber under pressure, generally of from three to ten atmospheres, or greater, and passes into the arc flame or is acted on by the arc flame and the resultant materials discharge through the small opening which is of such constricted area and short length that the velocity of the gas flow is greatly increased so that the gas passes from the arc flame through the openinp in the shortest possible time and is expanded and cooled substantially instantaneously. The tip of the upper electrode is preferably disposed in the throat 7., which is made as short as possible, so that hot gaseous matter passes at great velocfrom contact with the arc flame, directly immediately into the cooled expansion hods than those set forth hereinbefore maybe employed for cooling the hot gaseous medium. The are itself may be interrupted P that it is extinguished for brief time during a cycle, and during this time the products will cool with great rapidii nition of the 7 etc.

ing may be chosen as desirable. The reignition of the long are, however, presents certain dilliculties in practice, and, instead of letting the arc go out, I prefer to manipulate the power supplied to the are. so that the usual fat arc of high energy, which l employ, is reduced to a thin line arc, merely sufiicient to keep the are burning. This may be accomplished either by simply greatly reducing, the energy supplied to the arc, or by changing the form oi energy to higher voltage and lower ainper age, or use of both simultaneously. lly manipulating the energy supply, fat arcs and thin arcs may be caused to succeed each other at suitable frequency to produce the desired rapid cooling effect. When the arc is reduced to the thin line, the heat supply to the gaseous matter is abruptly interrupted and the temperature of the gaseous matter falls abruptly. The supply of material under pressure to be acted on by the arc may be supplied continuously or intermittently in time with the interruptions oi the fat are.

It is understood that the electrodes are connected to a suitable source of electrical energy to produce the are and that the arc is controlled by suitable electrical apparatus, such as both ohmic and inductive resistance, This is set forth in my prior Patent No. 1,056,830, but it is to be understood that I do not limit myself to the forms of electrical control there shown. it is also to be understood that one or both of the electrodes are movable longitudinally, so that. they may be brought into contact or proximate contact to start the are, after which they are separated the required distance to produce the desired are flame.

While this invention is particularly adapted to the fixation of nitrogen, which may be accomplished by introducine' air, or mixture of oxygen and nitrogen, um or pressure into the furnace chamber to produce oxides of nitrogen, it is to be understood that it is not limited to such use, since it may be used to combine nitrogen and hydrogen to form ammonia gas, or to combine carbon with nitrogen to form cyanogen gas and other compounds.

I claim:

1. The process of 'treatinr a mixture or materials to produce ot er forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action oi an electric arc flame whereby gaseous matter produced, and immediately and abruptly coolingthe gaseous matt/er out of contact with the are by concurrently subjecting it to two or more cooling methods.

2. The process of treating; a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure to an electric arc flame whereby lOU Ill)

litztl other forms of material are produced, removing the resultant material from the arc and simultaneously and rapidly cooling the resultant gaseous material by concurrent expansion and conductive cooling thereof.

The process of treating a mixture of materials to produce other forms of materials, whichcomprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc whereby other forms of material are produced and very hot resultant gaseous matter is produced removing the hot resultant gases from the arc and simultaneously, and rapidly expanding and cooling the hot resultant gaseous matter to reduce the temperature thereof below the temperature at which any great percentage of the resultant gaseous matter will dissociate.

4. The process of treating a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc flame whereby very hot resultant gaseous matter is produced and abruptly and concurrently expanding and cooling the gaseous matter as it leaves the iiame to reduce its temperature.

5. The process of treating a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc flame whereby very hot resultant gaseous matter is produced and abruptly reducing the temperature of'the gas as it leaves the flame to a temperature at which no great percentage of the gas will dissociate, by subjecting the gaseous matter to a plurality of cooling methods acting concurrently.

6. The process of treating a mixture of materials to produce other terms of mat rial, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc flame whereby very hot resultant gaseous matter is produced, and immediately thereafter abruptly expandingthe gaseous matter and contacting it with a cool surface whereby its temperature is abruptly reduced.

7. The process of treating a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc in the presence of suitable agents to increase the conductivity of the subjected mixture removing the resultant gases from the are flame and abruptly expanding and cooling the resultant gaseous matter as it leaves the flame.

8. The process of treating a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric presobtains.

9. The process of treating a mixture of T materials to produce other forms of material,

which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc in a closed vessel and discharging the resultant gaseous matter immediately thereafter from the are through a small orifice into a cooled chamber in which a much lower pressure obtains, I and concurrently contacting the gaseous matter with a cooling medium.-

' 10. The process of treating a mixture of materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc whereby very hot resultant gaseous matter is produced and immediately thereafter removing the matter from the are expanding the gaseous matter, contacting it with a fluid cooling medium and contacting it with a cooled surface.

11, The process of treating a mixture of materials to produceother .forms of material, I

which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc whereby very hot resultant gaseous matter is roduced and immediately thereafter expanding the gaseous matter, contacting it with a fluid cooling medium, contacting it with a cooled surface and reducing the temperature of the are.

12. The process of treating a mixtureof materials to produce other forms of material, which comprises subjecting the mixture under pressure greater than atmospheric pressure to the action of an electric arc in a closed vessel, discharging the resultant hot gaseous matter immediately thereafter from the are through a small orifice into a cooled chamber in which a much lower pres sure obtains and directing'a stream of cooling media into the discharging gaseous matter.

13. The process of producing oxide of nitrogen which comprises subjecting a mixture of oxygen and nitrogen under pressure greater than atmospheric pressure to the action of an electric are removing the resultant oxides from the are and immediately I v thereafter expanding and cooling the re sultant oxids to lower the temperature thereof to prevent dissociation and decomposition.

14-. The process of producing oxide of nitrogen which comprises subjecting a mixture of oxygen and nitrogen under pres sure greater than atmospheric pressure to the action of an electric are removing the resultant oxides from the arc and imme diately thereafter abruptly expanding the resultant oxids and bringing them into contact with a cool surface.

15. The process of producing oxids of nitrogen which comprises subjecting a mixture of oxygen and nitrogen under pressure greater than atmospheric pressure to the action-of an electric arc in the presence of suitable agents to increase the conductivity of the subjected mixture removing the result-ant oxides from the arc and abruptly expanding and cooling the oxids produced to prevent dissociation and decomposition.

16. The process of producing oxids of nitrogen, which comprises subjecting a mixture of oxygen and nitrogen under pressure greater than atmospheric pressure to the action of an electric arc flame whereby oxids of nitrogen are formed removing the resultant oxides from the arc and immediately thereafter expanding the oxids and contact ing them with a flllld cooling medium.

26 17. The process of producing oxids of nitrogen,which comprises subjecting a mix ture of oxygen and nitrogen under pressure greater than atmospheric pressure to the action of an electric arc flame whereby oxids oi 30 nitrogen are formed and immediately thereafter expanding the oxids, contacting them with a fluid cooling medium, and reducing the temperature of the arc.

18. The rocem of producing oxids of nitrogen, which comprises subjecting a mixture of oxygen and nitrogen under pressure greater than atmospheric pressure to the action of an electric arc flame whereby oxidsof nitrogen are formed and removing the 40 oxids from the arc and then immediately expanding them, removing heat therefrom by conduction and contacting them with a fluid cooling medium; 7

19. An apparatus of the character described, comprisin a closed vessel, means I for producing an e ectric are entirely within said vessel, means for introducing materials 'into said vessel under pressure so that they are subjected to the arc and an expansion 'chambercommunicating with said vessel through a small orifice.

20. An apparatus of the character de-' scribed, comprising a closed vessel, means for producing an electric are entirely within '55 said vessel, means for introducing materials into said vessel under pressure so that they are subjected to the arc, and a water cooled expansion cham'ber communicating with said vesselthrough a small orifice.

2L An apparatus of the character described, comprising a closed vessel, electrodes in said vessel between which an arc is formed, means for introducing material under pressure into said vessel so that it is subjected to the are and an expansion chamber communicating with the vessel through a small orifice, the orifice being disposed adjacent to and formed partly by one of said electrodes. I

22. An apparatus of the character described, comprising a closed vessel, electrodes in said vessel between which an arc is formedfmeans for introducing material under pressure into said vessel so that it is subjected to the arc, a water cooled expansion chamber, and a water cooled throat on said chamber connecting the chamber with the vessel, one'of said electrodes and said throat cooperating to form an orifice through which the material passes at high Velocit l 23. niapparatus of the character described, comprising a closed vessel, electrodes in said vessel between which an arc is formed entirely in saidvessel, means for introducing material under pressure into said vessel so that it is subjected to the arc, an expansion chamber communicating with said vessel through a small orifice through which gaseous matter passes from the vessel to the expansion chamber and means for directing a stream of cooling material into the gaseous matter as it passes through said orifice.

24. An apparatus of the character described, comprising a' closed vessel, electrodes in said vessel between which a are is formed, means for introducing ma erial under pressure into said vessel so that it is subjected to the arc, an expansion chamber communicating with said vessel through a small orifice through which gaseous matter passes from the vessel to the expansion chamber, and means in the expansion chamber for directing a stream of cooling material into the discharging gaseous matter at the orifice.

25. An apparatus of the character described, com rising a closed vessel, electrodes in sai vessel between which an arc is formed, means for introducing material under pressure into said vessel so that it is subjected to the arc, a water cooled expansion chamber communicating with said vessel through a small orifice through which gaseous matter passes from the vessel into the expansion chamber said orifice being partly formed by one of said electrodes, and'means in the expansion chamber 'for directing a stream of cooling material into the gaseous matter entering the expansion chamber.

In testimony whereof, I have hereunto set my hand.

HARRY D. RANKIN. 

